Appearance of tau-2 immunoreactivity in glial cells in human brain with cerebral infarction.

Appearance of tau epitopes in ischemic foci was investigated immunohistochemically on a series of autopsied human brains using a panel of anti-tau antibodies. While neurons were immunopositive for Alz-50, microglia and oligodendroglia around ischemic foci abundantly contained tau-2 immunoreactivity. Some astrocytes contained tau-2 immunoreactive granules in their cytoplasm. This difference suggests that neurons and glia react differently to an ischemic insult by exhibiting different tau epitopes. Immunohistochemical visualization tau-2 epitope represents its conformational change, as was reported with neurofibrillary tangles of Alzheimer type. Lack of argyrophilia in any of these tau-immunoreactive cells distinguishes them from tau-immunoreactive structures seen in various neurodegenerative disorders.